performance muffler sound on GN

[soundguy]

I am looking at replacing the stock exhaust on my '87 GN with maybe a flowmaster 3 chamber muffler but concerned about how it will sound on the V6. I dont want to make it sound like the riceburners around town as that sound is just flat out annoying. Dont want my car sounding like a weedwhacker. Has anyone used a flowmaster on theirs or have any suggestions on a good muffler to lower the back pressure and still sound good ?
I also noticed that the stock manifold has one chamber that dumps right to the turbo inlet instead of meeting up with the rest before hand. This seems very inefficient. Do the after market headers do the same or are they made more as I see it "correctly"?
Thanks for any insight on this

 

[jshilli1]

My T-type has 2 flowmasters on it. Everything I've read says Flowmasters + Turbocharger = not good combination because of the flowmaster technology. That said, it definitely does not sound like a rice burner. Sounds like a deep, throaty, V8 muscle car.

 

[soundguy]

forgot other concern. I had a bad experience when I replaced the stock muffler with a less restrictive one on my 98 f-150 that the transmission started slipping. Would this be a problem again without any other changes done or is the hydromatic tranny not susseptable to lower backpressure for the smoother shifts.

 

[rtviper]

I removed a Borla from my car and put on a dynomax ultra flow bullet. Really sounds a lot better then the Borla much deeper sound. Single 3.5 inch exhaust exit in front of the rear tire

 

[CanGN]

I also am running the dynomax race bullet..single 3"..sounds great

 

[VinsGN]

I'm running a 3" single pipe to a 40 Series Flowmaster muffler with dual 2.5" outlets (muffler in stock location). I love the deep sound with no drone.

Question: How could a Flowmaster not be good for a turbo car? There’s nothing in them but a couple sound baffles.

 

[1 RARE T]

Turbo cars work the most efficient with least amount of back-pressure. Engines are just big air pumps. More air in, more out = more power.

Flowmasters are not a straight thru design.

forgot other concern. I had a bad experience when I replaced the stock muffler with a less restrictive one on my 98 f-150 that the transmission started slipping. Would this be a problem again without any other changes done or is the hydromatic tranny not susseptable to lower backpressure for the smoother shifts

Changing the muffler made the trans. slip? I don't think so.

 

[Ormand]

The flowmasters are designed to muffle by reflection of pulses back and forth between the baffles. Since the turbo smooths out the pulses, before they get to the muffler, the design isn't right for a turbo engine. And since the baffles are in the flow path, they are a slight restriction, and a straight throught muffler will work a little better on our Buicks.
As to the headers- look again. The flow from the driver's side comes through the cross over, and into the passenger side header. Then that picks up the cylinders on the passenger side, and feeds all flow to the turbo. It would be nice if both sides could feed a common collector, and let that be the turbo feed line, but trying to fit that around power steering, A/C, and the other stuff under the hood on a street car would be nearly impossible. Look at ATR's headers, see if you like that any better. Still does more or less the same thing.

 

[rodman99999]

ATR mufflers

ATR's 3" SingleShot system(had one-sold it in here) has a REALLY throaty big block sound, and straight-thru design. I replaced it with their 2.5" dual set-up, which still has a nice throaty sound(but quieter), but doesn't drone at cruising speeds. The PitBull mufflers are the best design(straight thru) for turbo use(and available in stainless too). As stated earlier: open exhaust works best with a turbo, and these are so close: it's difficult to tell the difference(I've got a dump as well)!!

 

[rodman99999]

headers

Forgot the other part of your question. Both ATR and Kenne-Bell have headers that blend the flow of the right bank into the turbo-feed tube(to smooth out the flow) as you mentioned was your concern. The primaries are a bit smaller on the Kenne-Bells(1.125" K/B, 1.250" ATR) which should keep the velocities up better on a closer-to-stock motor. Stock headers will get you into the 10's, if they're not cracked.

 

[chiphead]

Run them open!!

I don't have muffler one on my car. Only thing that is in the pipe is a CAT. Car sounds great! I actually ran the car with the downpipe disconnected, to troubleshoot only, and I was suprised at how quite everything was. I guess the turbo wheel really eats up the noise.

 

[rodman99999]

A stock cat is a major source of backpressure though! Try the noise level at WOT (with the cat off), and no further exhaust, on for size. OOOOOEEEE

 

[gbsean]

that sound is awesome...even better when the honda in your rearview mirror is getting smaller

 

[GN/GTO]

ATR single shot the only way to FLY!!!

 

[Pats-GN]

I've got the Hooker catback with the aerochamber mufflers. Its got a nice mellow tone, a little louder than stock. Not raspy or "rice" sounding. Good system for the money.

 

[turbo2nr]

I think the Kenne Bell headers have been gone for about five years now

So, who has some new headers ready. I've read about this and that prototypes. Any done yet??

 

[sr71gn]

since i bought my first gn in 1987 i always run no cat or mufflers--everyone loves the sound

 

[alvin87gn]

wont that give you some KILLER drone man? and just who told you a new muffler made yer tranny slip?
guess you didnt replace the muffler bearings when you installed that new one, oh yeah, dont forget to check the blinker fluid, hehe

 

[soundguy]

no one told me, it was experienced in 2 vehicles. Evidently the newer vehicles use the backpressure to smooth out the shifts. The first car I thought it was mere coincidence, but it happened on my truck when I put the flowmasters on it.

 

[Silver 'T' Top]